Cutting Corners

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Cutting Corners:
Derek Jones takes a short cut approach to hand veneering that’ll save you a packet

Derek Jones takes a short cut approach to hand veneering that’ll save you a packet

We spend half our time each month steering readers towards more traditional ways of working,
the reason being that it will often be the most accessible and sometimes the most rewarding way of going about things.
There are of course numerous modern alternatives to tackle the same problem and for me it’s the blend of both the old and the new that invariably gets used. Dig deep into the history books and you’ll generally find that the best modern techniques will have been adapted from those from the past, it’s the natural evolution of a process and I know of very few creative people that stay in one mode of work permanently. This technique for laying up veneer is one such method.
It came from the workshop of our profiled artist in F&C issue 245, antique furniture restorer John Hartnett. It also happens to be my first real foray into working with modern 0.7mm thick veneers. Before that
if I wanted a piece of veneer I had to search among a pile of envelopes stuffed full of reclaimed fragments of period specimens a great deal thicker than a measly 0.7mm.

Thermo-logically speaking 
Hide, or more accurately put, protein glues require two things to make them work; heat and moisture. On their own either of these two elements will affect the properties of the glue and nearly always to its detriment. Equally, having too much of one and not enough of the other will result in a similar outcome. But it’s not just protein glues that succumb to this treatment. White glue, or PVA as we like to call it, will also react to a combination of heat and moisture. The effects if brought about quickly and simultaneously can be used to create your own iron-on veneer.

Thin on the ground
For reasons that should become obvious select an interior grade of PVA and not a waterproof variety that’s intended for external use. Alternatively use a pre-mixed bottled hide glue. Put a quantity of the glue in a jar and add approximately the same amount of water to a ratio of 50/50. Keep the lid to the jar and have a jug or separate vessel of clean water from the tap on standby. Give the mixture a good stir and select a clean brush that won’t shed hairs the moment you show it a wet surface. I’ve found that buying cheap paintbrushes is a false economy even for paint stripping.

Use water-based interior grade PVA or hide glue for your adhesive

Start off with a 50/50 mix of glue and water

Real liquid hide glue
You can use this technique if you use hot hide glue as well. Just make a slightly thinner batch of glue and add urea to the ratio of between 10 and 40% to keep it liquid at room temperature and therefore prevent it from gelling as it cools in the jar. Split the water content of the glue mixture to incorporate around 30% strong beer to enhance pore penetration. 

Urea can be used to produce a hide glue that remains liquid at room temperature

Cut and paste
It’s easier to work with large pieces of veneer so start with cutting a leaf or two of veneer that will cover all the separate pieces you require. If you are working with burr veneer there’s no harm in wetting it on both sides and placing the individual leaves between some moist newsprint sandwiched between two flat boards under sufficient pressure to keep the pack flat. Over night should do the trick. If you are using light timbers then substitute newsprint for either brown paper or white packing paper as the ink can stain the veneer. This is typically done when hammer veneering with hide glue to make the material more pliable and release some of the tension within the fibres. It’s not always necessary if you are using straight grain material.
Prepare a pasting board by laying down some paper and spraying it with water. Then spray one side of the veneer with water and place it wet side down onto the wet paper. The veneer will want to curl up along the length of the grain so apply some tape to the ends and wrap it around the pasteboard. Immediately apply a liberal coat of your thinned down glue. The veneer should start to flatten down, maybe not completely but flat enough to prevent it from curling further or splitting. What you’re looking to do here is flood the pores with glue so you can afford to be a little firm with your brush technique.

Wet the face side of the veneer with water

Apply the first thinned coat of glue to the back side of the veneer

Cut your components oversize from the glued-up leaf as you need them

Rinse and repeat
When you have an even covering rinse the brush in the pot of water and allow the glue to dry on the veneer. If your intended substrate is to hand you can apply a coat of the glue to that surface at the same time. Now add a little more glue to the mixture to achieve something like a 3:1 ratio and recoat the veneer and substrate. The second coat should dry a lot quicker. If the surface has attracted dust particles pick them off as you go or remove them later with some abrasive paper when it’s dry. Inevitably the veneer will stick to the paper but it’s not a problem as they can be separated quite easily with a knife. When the glue has dried the veneer can be stored in a dry condition indefinitely. In this state you can recut the leaves to suit the finished size. I typically find three coats of adhesive on both surfaces is sufficient. Be prepared to experiment, however, as not all glues react the same way.
It’s highly likely if you’re using PVA that you will see evidence of black spotting under the glue as it dries. Minute iron particles are the likely cause deposited into the veneer during the cutting process in the factory. It’s quite normal and probably happens when you use PVA to fix veneer in a press but of course you never see it. It shouldn’t show through to the face side.

Heat treatment
To stick the veneer to your chosen substrate you’ll need those two magic ingredients I mentioned earlier, heat and moisture. A domestic iron is a good source of heat and a damp sponge works for the latter. Lightly dampen either the surface of the substrate or the veneer, whichever is most convenient, and position the veneer in place. Apply heat with the iron and gently move it across the surface. You may hear a faint hiss as the water steams on contact with the iron. If you’re using hide glue work a cold iron behind the hot one to cool the glue down and cause it to gel. You may have to adjust the amount of moisture applied depending on how long in advance the veneer has been prepared. You can do this by wiping the sponge over the show side of the veneer. The bond is complete as soon as the surface has cooled. If you discover bubbles in the surface just apply heat and maybe a little moisture to the area and repeat the process. Experiment first before attempting to veneer large areas using this technique and ensure that the substrate is flat and free from defects. MDF or ply is a perfect choice. 

A light application of water from a damp sponge is sufficient

Apply heat and firm pressure with a domestic iron

Edge trimming
Just like shop bought iron-on veneer you can pretty much trim the workpiece as you go. Press a block of scrap material on the face of the freshly laid veneer and gently score it from below with a craft knife to remove the waste. A cabinet scraper or better still a little scraper plane will trim the veneer flush with the face of the board. Don’t try and do it with a chisel or block plane, you’re bound to hit a patch of cranky grain and tear the veneer from the board.

Make a series of light scores to remove excess rather than one heavy cut

A scraper plane can level and square the corners of the veneer with less risk of tear-out

Veritas scraper plane

Overlay jointing
You can use the principles of hammer veneering to lay sections of veneer together. Iron the first piece to the substrate leaving a small section loose at the joint end, 5 or 10mm should be fine. Lay the second piece of veneer to be joined so it overlaps the loose end of the first piece. Iron it into place moving away from the joint so you have two loose ends. Cut through both pieces of veneer at the same time with a craft knife, peel away the waste and iron the loose ends into position. This works in any direction and allows you to work with oversized sections. A good way of checking if your veneer has stuck is to wipe the area over with meths. It won’t stay wet as long as water will but will cause any loose patches to bubble up slightly. This is a good initial test to determine whether your glue mix has been a success. If not it’s probably time to apply another coat.

Lay the second piece directly over the first piece and cut through them at the same time to make the joint

Peel away the offcut from beneath and iron the two edges down

Test with meths to gauge the strength of your glue layer

Quick fire samples
One of the advantages of this cut and paste technique is being able to lay up sample boards very quickly. You quite literally cut and paste as you go without the need of a press or vacuum bag. This sample board was cut, laid and finished, one process after the other without stopping. Having a repeat pattern and a template speeds things up but even random shapes are quick to do.

The finished sample board laid and polished in just a couple of hours

Create a template
Use geometry and not measurements to lay out a template, it’s quicker and more accurate. MDF is a good choice for a small one-off design but consider something a little more robust for large or repeat projects. For continuity of colour and appearance when the veneer is polished it helps to mark the template and make sure it is always laid on the veneer in the same direction. Transfer the mark onto the veneer piece so you can orientate each piece on the board accordingly. For this pattern I laid a couple of diagonal lines on my board and worked from the centre outwards, the lines are only a rough guide. I had decided that the infill sections would be 8mm wide so laid the first two diamonds over the line by about 1mm as the shapes distort slightly while they’re being stuck down. Be careful not to touch the iron onto the glued surface of the substrate or swamp it with water. This is more of a problem when using hide glue as the iron will pick up glue and then stick to the next object it touches. Try to keep the iron moving all the time, in a small area work in tiny circles.

For a repeat pattern consider making a template that’s oversize

Make a note of the direction of the grain to ensure continuity of colour when finish is applied

Set the shape slightly over the layout lines

Complete the background pattern first before trimming

Trim to fit
With all the diamonds stuck down I then took a steel ruler and working on one edge at a time cut the edge of the diamonds back to my original layout line. The pre-prepared section of inlay was then placed firm against the ledge to gauge the opposite side of the groove. Use the inlay as a marker and not a straight edge. The waste can be peeled away with a sharp chisel. 

Create a straight edge to align all the points of the diamonds along one line

Use a second template or the inlay material to mark up the opposite edge of the groove

Trim away any excess material

Quick repairs
Repairs are easy to make using the overlay technique if you inadvertently lose a corner. Keep a small supply of leftover veneer. Patch in a piece oversize and then trim it back.

Carry out any repairs with offcuts of veneer

Pre-finish if you can
The veneer is quite vulnerable at this stage until the infill sections are laid and the panel is housed in a frame. Levelling has to be done carefully. I found that wrapping abrasive around a flat block and sanding with the fold perpendicular to my stroke the most effective method. Use anything coarser than 180 grit and you might be pushing your luck, remember you only have 0.7mm of veneer to play with and the scratch pattern from each grade of abrasive has to be removed before moving onto the next.
Now is also a good opportunity to carry out any finishing. I used a brush to achieve a good even covering of shellac before finishing with a rubber, French polish style, and wax. Any excess was scraped away from the grooves so as not to interfere with gluing later.

Adopt a linear approach to sanding

Take the opportunity to pre-finish where you can

Raised inlay
The strip of bog oak used for the inlay was repeatedly re-sawn and planed flat on one face after the diamond pattern had been trimmed back to fit. It’s thicker than the veneer by 2mm so effectively raised from the surface of the board. I laid long strips first in one direction and then cut the short sections in between to complete the pattern. It was possible to lay the entire board up dry shooting the identical mitres on the edge of a shooting board with a small mitre plane, a block plane would work just as well. The infills were glued into the grooves at the same time and a flat board placed on top with clamps for pressure while the glue dried. Had I chosen a material the same thickness as the veneer I would have laid it in the same way as the diamonds and finished the board at the end. The excess glue was easy to remove from the polished surface of the diamonds.

Use a shooting board and plane to achieve good clean mitres

If the infills stay put without glue it’s a good sign

Use a wide block to sand the raised infills so you don’t damage the polished background

A soft beeswax polish combined with a little black sawdust from sanding is a no-nonsense finish for dark timbers like bog oak

Use a brush when the wax has dried and buff to a shine

Pros and cons
I’m not suggesting for a minute that this cut and paste technique is better than conventional hammer veneering or veneering in a press or vacuum bag but it does have some advantages; the main one being that you don’t need any special equipment to do it. The results are instant and repairs or adjustments happen in real time as you work so there’s no waiting for glue to go off once the initial pasting has been done. As hand veneering goes it’s also very clean and you can make as much or as little as you require without having to buy a roll of iron-on veneer from a supplier that may not be a good match for the rest of your project. As for the down side, you might find that 0.7mm thick is a little delicate for edges and although I prefer to use thicker veneers whenever I can they don’t work as well with this method; the pre-gluing tends to cause the veneer to warp and the amount of heat required to lay them flat consistently is hard to achieve with a domestic iron. That said it’s a fun way to experiment with surface patterns and ideal for mock-ups and sample boards.

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